The design of many large vehicles, in particular cab-over-engine trucks, does not allow easy access into the cab of the vehicle. Often, the cab is positioned at a substantial height from the ground, making it nearly impossible for a passenger to just "step up" into the cab from the ground and requiring the passenger to jump out of the cab to the ground. This positioning makes access to and from the cab somewhat hazardous. Therefore, steps or some other type of foot support structure are necessary to allow a passenger to climb up into the cab and walk out of the cab. However, there is often little space available beneath the door to the cab for providing steps or the like because the door often is positioned almost directly above a forward wheel the truck.
Also, steps or the like that protrude from the side of the vehicle are unsatisfactory from an aerodynamic standpoint because they likely will decrease fuel mileage and increase emissions. Therefore, a need exists for a stairway that provides comfortable and safe access to and from the cab, while having reasonable aerodynamic characteristics.